Fig. 1: Proposed mechanism for explaining the shift from drought to pluvial from the perspective of soil moisture−atmosphere feedbacks.

Here, plus (+) and minus (‒) indicate positive and negative relations, respectively. The colors show the soil moisture‒latent heat flux‒precipitation (blue), the soil moisture‒temperature (red) and the soil moisture‒moisture convergence‒precipitation (yellow) feedback loops. a Local moisture transport processes: (I) Soil desiccation increases sensible heat flux, and the increasing sensible heat flux further enhances temperature. (II) Hotter air in turn enhances the evaporative demand and thus latent heat flux if water is sufficient. (III) As latent heat flux and temperature rise, atmospheric water-holding capacity and moisture content increase. (IV) Pluvial is likely to be triggered by the increase in actual atmospheric moisture content. (V) Pluvial prevents further soil desiccation. b Remote moisture transport processes: (I) Soil desiccation enhances low-level flow convergence to increase moisture. (II) As moisture in air rises, pluvial is likely to be triggered. (III) Pluvial prevents further soil desiccation. Ocean is the main moisture source in the remote moisture transport processes.